Composite nozzle

ABSTRACT

A composite turbine nozzle is provided with an erosion resistant inner surface.

O United States Patem 3,737,247 Horning June 5, 1973 [54] COMPOSITENOZZLE [56] References Cited [75] Inventor: William A. Homing, LosAngeles, UNITED STATES PATENTS Calif.

1,378,746 5/1921 Wheeler ..415/186 [73] Asslgnee: The GarrettCorporatlon, Los An- 3 030 071 4/1962 s h -Jn .415/196 geles, Calif.3,042,366 7/1963 l-lolmquist ....4l5/214 3,063,673 11/1962 Johnson..415/205 [221 Filed 1971 FOREIGN PATENTS OR APPLICATIONS [21] App].No.: 133,002 19,632 0/1905 Great Britain ..415/212 55,579 11/1943Netherlands ..415/158 52 U.S. Cl. .415/195, 415/205, 415/212, PrimaryExamine, flemy R Raduazo 41 5/216 Attorney-A1bert J. Miller and John N.Hazelwood [51] Int. Cl. ..F0ld 1/08 [58] Field of Search ..415/195,196,200, ABSTRACT 415/186, 212, 214, 219, 217, 218, 216,158, A compositeturbine nozzle is provided with an erosion resistant inner surface.

14 Claims, 3 Drawing Figures PATENTEUJUN 5137s .r/WE/vrae TV/iL/AM A.Ham/W5;

when 3. 77mm J a m COMPOSITE NOZZLE BACKGROUND OF THE INVENTION Inradial inward flow turbine nozzles, erosion of the inner surface of thenozzle by dirt and/or liquid particles thrown outward by the turbinewheel blades can greatly reduce the life of the nozzle. Attempts toprovide a nozzle of erosion resistant material have proven to beuneconomical in view of the close dimensional tolerances required inorder to control the turbine flow rate through the nozzle passages.

SUMMARY OF THE INVENTION The present invention provides a compositenozzle having an outer nozzle ring of an easily machinable material toprovide close dimensional tolerances for the nozzle passage therethroughand an inner nozzle ring of erosion resistant material with slightlylarger nozzle passages therethrough and having relaxed tolerances.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial sectional view ofa radial inward flow turbine illustrating the composite nozzle of thepresent invention.

FIG. 2 is a sectional view of the composite nozzle portion of the radialinward flow turbine of FIG. 1 taken along line 2-2.

FIG. 3 is a sectional view of the composite nozzle of FIG. 2 taken alongline 33.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As illustrated in FIG. 1, theradial inward flow turbine generally comprises a torus assembly mountedbetween supports 12, 14 positioned on a turbine nozzle 16. Packings 18and may be provided between the nozzle 16 and the supports 12 and 14respectively. The nozzle 16 having an outer nozzle ring 17 may beconstructed of any easily machinable material, such as steel, which canbe fabricated to close dimensional tolerances. A turbine wheel 21including blades 22 is adapted to rotate between the nozzle 16 and aseal 24.

The inner nozzle ring 26, of an erosion resistant material such ascemented carbide, or other sintered material such as aluminum oxide, isprovided between the radial outward end of the turbine blades 22 and theouter nozzle ring 17. The inner nozzle ring 26 may be held in positionby a groove 28 in the nozzle 16 and/or by a plurality of screws 30 (andwashers 32) threaded into the outer nozzle ring 17. An elastomeric seal,such as silicone rubber cement, may be provided between mating surfacesof the outer nozzle ring 17 and inner nozzle ring 26. The seal 24extends upward between the nozzle 16 and the turbine housing assembly34. Shims 36 and 38 can be provided between this upward extending seal24 and the housing assembly 34 and inner nozzle ring 26, respectively.

As shown more clearly in FIGS. 2 and 3, at least one row of spacednozzle passages 40 extend around the outer nozzle ring 17. Two rows ofindividually staggered passages 40 are illustrated. These passages 40may be provided with an enlarged tapered inlet section 42 to facilitateflow entry. Aligned with the individual passages 40 in outer nozzle ring17 are a plurality of individual passages 44 in the inner nozzle ring26. With the nozzle 16 including outer nozzle ring 17 constructed of aneasily fabricated material such as steel,

the nozzle passages 40 can be machined to a precise dimension holdingclose tolerances, sufficient to control the turbine flow rate asrequired. The inner nozzle ring 26, being constructed of an erosionresistant material, is not susceptible to being machined to closetolerances and, accordingly, the flow area of individual nozzle passages44 should be slightly greater than the flow area of individual nozzlepassages 40.

For example, if the diameter of nozzle passages 40 is designated as D,having a'tolerance of T,, the diameter D, of nozzle passages 44 would beslightly greater than D and have a tolerance T considerably greater thantolerance T,, with the limitation that (D T is still greater than orequal to (D, T,).

In this way the erosion resistant material is provided in the area whereit is required, thus greatly enhancing the nozzle life. In addition,erosion damage to the turbine wheel is also reduced. The compositenozzle can be economically produced, since relatively large dimensionaltolerances can be accommodated by the erosion resistant material. Thenozzle throat which controls the turbine flow rate is incorporated intothe outer nozzle ring which can be fabricated to close dimensionaltolerances.

While specific embodiments of the invention have been illustrated anddescribed, it is to be understood that these embodiments are provided byway of example only and that the invention is not to be construed asbeing limited thereto, but only by the proper scope of the followingclaims.

What I claim is:

1. A composite nozzle for a radial inward flow turbine wheel comprising:

an outer nozzle ring having a plurality of spaced nozzle passagesextending therethrough; and

an inner nozzle ring of an erosion resistant material disposed radiallyinward from the outer nozzle ring and having a plurality of spacednozzle passages extending therethrough individually aligned with thespaced nozzle passages of said outer nozzle ring to receive a flow offluid therefrom, said inner nozzle ring radially disposed around saidturbine wheel to deliver a flow of fluid thereto.

2. The composite nozzle of claim 1 wherein the spaced nozzle passages ofsaid inner nozzle ring have a greater cross-sectional flow area than thespaced nozzle passages of said outer nozzle ring.

3. A composite nozzle for a radial inward flow turbine wheel comprising:

an outer nozzle ring having a plurality of spaced nozzle passagesextending therethrough, said outer nozzle ring spaced nozzle passageshaving a crosssectional flow dimension D with a dimensional toleranceT,; and

an inner nozzle ring of an erosion resistant material disposed radiallyinward from the outer nozzle ring and having a plurality of spacednozzle passages extending therethrough individually aligned with thespaced nozzle passages of said outer nozzle ring, said inner nozzle ringspaced nozzle passages receiving a flow of fluid from said spaced nozzlepassages of said outer nozzle ring and having a crosssectional flowdimension D, greater than D and with a dimensional tolerance T greaterthan T such that D, T is at least equal to D, T, said inner nozzle ringradially disposed around said turbine wheel to deliver a flow of fluidthereto.

4. The composite nozzle of claim 3 wherein D T is greater than D T y S.The composite nozzle of claim 3 and in addition elastomeric seal meansdisposed between said outer nozzle ring and said inner nozzle ring.

6. The composite nozzle of claim 3 wherein the spaced nozzle passages ofsaid outer nozzle ring have an enlarged tapered inlet section.

7. The composite nozzle of claim 3 wherein said plurality of spacednozzle passages comprise two circumferential rows of staggered nozzlepassages.

8. The composite nozzle of claim 3 wherein said inner nozzle ring is asintered material.

9. The composite nozzle of claim 5 wherein said elastomeric seal meansis a silicone rubber cement.

10. The composite nozzle of claim 1 wherein the spaced nozzle passagesextending through said inner nozzle ring are substantially the samecross-sectional configuration as the spaced nozzle passages extendingthrough said outer nozzle ring.

11. The composite nozzle of claim 3 wherein the spaced nozzle passagesextending through said inner nozzle ring are substantially the samecross-sectional configuration as the spaced nozzle passages extendingthrough said outer nozzle ring.

12. In combination:

a radial turbine wheel; and

a turbine housing to rotatably support said turbine wheel therein anddirect the flow of fluid thereto, said turbine housing including acomposite nozzle radially disposed around said turbine wheel to directthe flow of fluid from said housing to said radial turbine wheel;

said composite nozzle comprising an outer nozzle ring having a pluralityof spaced nozzle passages extending therethrough and an inner nozzlering of an erosion resistant material disposed radially inward from saidouter nozzle ring and having a plu- I ralityof spaced nozzle passagesextending therethrough individually aligned with the spaced nozzlepassages of said outer nozzle ring, the flow of fluid from said turbinehousing to said radial turbine wheel being first through the spacednozzle passages of said outer nozzle ring and then through the spacednozzle passages of said inner nozzle ring. 13. The combination of claim12 wherein the spaced nozzle passages of said inner nozzle ring aresubstantially the same cross-sectional configuration as the spacednozzle passages of said outer nozzle ring.

14. The composite nozzle of claim 13 wherein the spaced nozzle passagesof said inner nozzle ring have a greater cross-sectional flow area thanthe spaced nozzle passages of said outer nozzle ring.

1. A composite nozzle for a radial inward flow turbine wheel comprising:an outer nozzle ring having a plurality of spaced nozzle passagesextending therethrough; and an inner nozzle ring of an erosion resistantmaterial disposed radially inward from the outer nozzle ring and havinga plurality of spaced nozzle passages extending therethroughindividually aligned with the spaced nozzle passages of said outernozzle ring to receive a flow of fluid therefrom, said inner nozzle ringradially disposed around said turbine wheel to deliver a flow of fluidthereto.
 2. The composite nozzle of claim 1 wherein the spaced nozzlepassages of said inner nozzle ring have a greater cross-sectional flowarea than the spaced nozzle passages of said outer nozzle ring.
 3. Acomposite nozzle for a radial inward flow turbine wheel comprising: anouter nozzle ring having a plurality of spaced nozzle passages extendingtherethrough, said outer nozzle ring spaced nozzle passages having across-sectional flow dimension D1 with a dimensional tolerance T1; andan inner nozzle ring of an erosion resistant material disposed radiallyinward from the outer nozzle ring and having a plurality of spacednozzle passages extending therethrough individually aligned with thespaced nozzle passages of said outer nozzle ring, said inner nozzle ringspaced nozzle passages receiving a flow of fluid from said spaced nozzlepassages of said outer nozzle ring and having a cross-sectional flowdimension D2 greater than D1 and with a dimensional tolerance T2 greaterthan T1 such that D2 - T2 is at least equal to D1 + T1 , said innernozzle ring radially disposed around said turbine wheel to deliver aflow of fluid thereto.
 4. The composite nozzle of claim 3 wherein D2 -T2 is greater than D1 + T1.
 5. The composite nozzle of claim 3 and inaddition elastomeric seal means disposed between said outer nozzle ringand said inner nozzle ring.
 6. The composite nozzle of claim 3 whereinthe spaced nozzle passages of said outer nozzle ring have an enlargedtapered inlet section.
 7. The composite nozzle of claim 3 wherein saidplurality of spaced nozzle passages comprise two circumferential rows ofstaggered nozzle passages.
 8. The composite nozzle of claim 3 whereinsaid inner nozzle ring is a sintered material.
 9. The composite nozzleof claim 5 wherein said elastomeric seal means is a silicone rubbercemenT.
 10. The composite nozzle of claim 1 wherein the spaced nozzlepassages extending through said inner nozzle ring are substantially thesame cross-sectional configuration as the spaced nozzle passagesextending through said outer nozzle ring.
 11. The composite nozzle ofclaim 3 wherein the spaced nozzle passages extending through said innernozzle ring are substantially the same cross-sectional configuration asthe spaced nozzle passages extending through said outer nozzle ring. 12.In combination: a radial turbine wheel; and a turbine housing torotatably support said turbine wheel therein and direct the flow offluid thereto, said turbine housing including a composite nozzleradially disposed around said turbine wheel to direct the flow of fluidfrom said housing to said radial turbine wheel; said composite nozzlecomprising an outer nozzle ring having a plurality of spaced nozzlepassages extending therethrough and an inner nozzle ring of an erosionresistant material disposed radially inward from said outer nozzle ringand having a plurality of spaced nozzle passages extending therethroughindividually aligned with the spaced nozzle passages of said outernozzle ring, the flow of fluid from said turbine housing to said radialturbine wheel being first through the spaced nozzle passages of saidouter nozzle ring and then through the spaced nozzle passages of saidinner nozzle ring.
 13. The combination of claim 12 wherein the spacednozzle passages of said inner nozzle ring are substantially the samecross-sectional configuration as the spaced nozzle passages of saidouter nozzle ring.
 14. The composite nozzle of claim 13 wherein thespaced nozzle passages of said inner nozzle ring have a greatercross-sectional flow area than the spaced nozzle passages of said outernozzle ring.